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British Aerospace, Airbus Ltd., Chester, UK manufactures the main wing box assembly for all current Airbus programs. Titanium interference fasteners are used in large numbers throughout these aircraft structures. On the lower wing skin of the A320 alone there are approximately 11,000 of this fastener type. Currently, the majority of these fasteners are manually installed using pneumatic or hydraulic tooling. British Aerospace engineers recognized the significant potential which automation offers to reduce these current labor intensive installation methods. Electroimpact proposed extending Low Voltage Electromagnetic Riveter (LVER) technology to the automatic installation of these interference fasteners as well as rivets. Close liaison between Airbus and Electroimpact engineers resulted in the development of an automated LVER based lockbolt installation system, which is currently undergoing evaluation.

This paper gives an outline of testing carried out in conjunction with Electroimpact to support the introduction of the A319/A320/A321 and A340-500/600 Panel Assembly Cells in Broughton, UK. Testing compared the percussion insert/EMR swaging of lockbolts with existing hydraulic installation methods. Tests included pre-load tension tests, ultimate tension load tests, tension fatigue tests, high-load lap shear fatigue tests, static lap shear tests, a pressure leak test, and metallurgical examination. Fastener configurations tested covered diameters from 1/4, 5/16, 3/8, and 7/16 of an inch. Joint materials conformed to ABM3-1031 (7150-T651 plate), stump-type lockbolts to ABS0550VHK (Huck LGPS4SCV), and collars to ASNA2025 (Huck 3SLC-C). Some pull-type lockbolts to ABS0548VHK (Huck LGPL4SCV) were also tested as noted.

Hand installation of 3/8", 5/16" and 1/4" diameter fatigue head style fasteners is required on some areas of 747 section 11 (center wing). The 3/8" diameter fasteners can require between 45-60 seconds to upset using conventional pneumatic riveting guns. As part of Boeing’s continuing effort to reduce cycle time and improve the factory working environment, a Boeing Quality Circle Team proposed using LVER technology as an alternative to conventional pneumatic percussion riveting hammers The hand operated HH500 system was developed in response to this request. The HH500 single shot upset reduces installation time as well as the noise levels and vibration experienced by the operators. The design of this system and the integration onto the factory floor are presented. The LVER forming rate is significantly higher than that of conventional pneumatic and hydraulic processes.

A new wing panel riveting cell capable of replacing tack fasteners and performing small repair jobs has been developed. Using two mobile scissor lift platforms with electromagnetic riveters mounted on each, the operators can access every portion of the wing panel without the use of ladders or platforms. This method minimizes fatigue, allows workers to carry all tools and supplies with them, meets current safety standards and minimizes coldworking of the components.